Fuel cells are well-known and are commonly used to produce electrical energy from reducing and oxidizing reactant fluids to power electrical apparatus, such as apparatus on-board space vehicles, transportation vehicles, or as on-site generators for buildings. A plurality of planar fuel cells are typically arranged into a cell stack surrounded by an electrically insulating frame structure that defines manifolds for directing flow of reducing, oxidant, coolant and product fluids as part of a fuel cell power plant. Each individual fuel cell generally includes an anode electrode and a cathode electrode separated by an electrolyte, such as a proton exchange membrane (“PEM”) electrolyte, as is well known.
It is also known that manufacture of PEM fuel cells involves a substantial break-in period after a fuel cell is assembled in order to get the fuel cell to achieve peak performance of a maximum, consistent current output at a specific voltage. Such break-in periods often exceed 100 hours of operation of the fuel cell. In a PEM fuel cell, the PEM electrolyte is typically secured between an anode catalyst layer and a cathode catalyst layer. The catalyst layers are known to be supported on carbon support materials to maximize surface areas of the catalysts available for contact with reactant streams, and to provide for flow of the reactant and product fluids to and away from the catalyst layers. The catalyst layers secured to such support materials are frequently characterized as either a cathode electrode or an anode electrode. The electrodes are secured on opposed sides of the PEM electrolyte to form a membrane electrode assembly (“MEA”), as is known in the art. A PEM electrolyte is an ionomer, and the electrodes may also include ionomers to facilitate ion movement through the MEA during operation of the fuel cell.
It is theorized that the electrodes, ionomers within the electrodes, and the PEM electrolyte are slowly wetted during the break-in period. By being fully wetted, ionic resistance of the MEA is reduced, and effective surface areas of the catalysts available for fuel cell electrochemical reactions are increased, thereby enhancing performance of the fuel cell. As fuel cells commence high volume production to meet transportation needs, however, such lengthy break-in periods are a significant, and unacceptable cost burden.
Accordingly, there is a need for an accelerated break-in procedure for a fuel cell that reduces a total time period necessary for bringing the fuel cell to peak performance.